Question 7 • Crowley Original Credit Chemistry B
A base is stronger when its conjugate acid has a higher pKa. The conjugate-acid pKa values increase in this order: pyridinium (about 5.2), hydroxylammonium (about 5.9), ammonium (about 9.3), and methylammonium (about 10.6). Therefore, the bases go from weakest to strongest as pyridine < hydroxylamine < ammonia < methylamine.
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